Improvement in shears for cutting off bar-iron



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Shears for Cutting off Bar-lro-m No. 146,846. Patengedulan.27,187@ E UNITED STATES PATENT FFIGE.

WILLIAM X. STEVENS, oF EAST nEooKrIELD, MASSACHUSETTS.

IMPROVEMENT IN SHEARS FOR CUTTING OFF BAR-IRON.

Specification forming part of Letters Patent No.1469846, dated January 27, 1874; application filed I November 3, 1873.

To all whom it may concern.'

Be it known that I, WILLIAM X. STEVENS, of East Brookfield, in the county of Worcester and State of Massachusetts, have invented Shears for Cutting Ofi' Bar-Iron, of which the following is a specication:

The object of my invention is to shear off bar-iron of larger size than has ever been so cut, and to shear` oi` common `sizes with greater `easeby ineans of' a cutting blade or die, D within the trunnion ot' one arm, B, of the slear, in' combination with a similar opposing blade or die, C, within or held by the other arm A, which incases and serves as bearing in which said trunnion of arm B revolves or oscillatcs.

As here shown, A is the body of the machine, made, most economically, of cast-iron. C is a sq'uare die of Steel, having holes cnt through it, to correspond to the .form and sive of iron `to be out, and is h eld securely in a recess of corresponding form in frame A. Dfis an opposing d ie `exactly corresponding to G, but held in the trunnion of oscillatin g arm B.

In Figure 1, D represents both dies (lh and l) as they stand before either die is turned in use. E is a collar secured to body A by means of bolts F, for the purpose of holding the dies or" blades 'C and D in contact, which it Vdoes by means of an annular bearing on A the outer face of lever B. The upper end of arm B is an arcof a circle from center `K of the trunnion, and supplied with gear-teeth, which, for sake of their strength, are made internal. Intthese teeth Works a pawl, Gr, hung upon the crank or eccentric H of shaft I, which is turned iii a bearing at the top of body A by means of a hand-lever, J. L `is a spring attached at one end to body A, and at the other end to pawl G, to press the end of pawl G into engagement vwith the teeth upon arm B. y

The dies represented in Figs. 1, 2, and 3 are for cutting oli' round iron from the size of the largest opening to O. i

Fig. 4 shows dies for cutting oii' rails; and Fig. .5 is a die suitable for cutting square and flat iron. l

One pair of dies may have many different volving shaft I by `power crank II draws pawlr y G back one tooth; then pushing against said tooth revolves the whole arm Bl and its die D through the minute arc of a circle` subtended by the base of said tooth; and each repetition produces the same result until the whole segment of teeth on arm B" pass beyond reach of pawlG, or until a bar ,'inserted in the dies has ubeen cut oit', when pawl G1 is held away from the teeth and arm B is returnedto position by hand; or the pawl may be swung over to point the other way, so as to cause the opposite edges of the dies to cut. Thus either side of the machine4 may be its front and the dies give double wear.

Fig. 3 shows the relative position ot' the cutting holes before and after work, C being stationary and D revolving, as indicated by the arrows.

For cutting barliron, I make the largest hole in the dies with oneedge of the hole at their center of revolution, K, to reduce to a minimum the leverage against me; and experiment has shown that common `iron severs when penetrated about one-fifth its diameter by the shear-blade; therefore, a segment of gear-teeth on arm B equal to an arc of ninety degrees is enough for practical purposes.

In the old form of shear a bolt large enough l to withstand the` Strain and wear of cutting must occupy the center, andwork cannot be brought nearer center than' is 'safe against breaking the steel die out at the bolthole; but by means of my inserted trunnioii being so large as to contain the whole die I produce a fulcrum so large that anysized iron whatever may be cut ofi", al1 parts being proportional without danger to the bearing; and by means of my crank, pawl, and gear combination I am able to multiply the leverage to an extent only limited by the power of each tooth to resist crushing.

I claim as my invention and Wish to secure by Letters Patentl. The combination in shears for cutting metal of the lever or shear arms A and B,

jointed, by means of a trunnion7 upon the lever B, entering and revolving in a, complete circular bearing of the lever` A (so held by means of the collar E and bolts F) with the dies or shearedges C and D Within the circular bearing of and held7 respectively7 by aforesaid levers A and B. 2. The. combination of lever A,toothed lever B, shaft I,- crank or eccentric H, and pawl G, substantially as shown and described.

WILLIAM X.- STEVENS.

Witnesses:

Mo's'Es HoBBs, J osIAH HoBBs. 

